In recent years, mobile communications have remarkably been in wide use and progress, and there are great expectations for mobile communications. The 3GPP has laid down new standards for the purposes of providing multimedia- and Internet-conscious systems, supporting data communications at high data rates, and establishing global common standards.
Radio communication standards of the 3GPP employ the AMC (Adaptive Modulation and Coding) technology for efficient data transmission.
According to AMC, dynamic changes in the line quality are adaptively addressed to effectively utilize radio channel resources for efficient data transmission. A data reception device measures the line quality and selects a modulation process and an encoding ratio for use in data transmission, i.e., an MCS (Modulation Coding Scheme), based on the measured line quality, and sends the MCS to a data transmission device. The data transmission device transmits data using the MCS.
At present, various studies are being made as to methods for appropriately selecting an MCS (see, for example, Japanese laid-open patent publication No. 2002-199033, Japanese laid-open patent publication No. 2002-320262, and PC(WO) No. 2002-527938.